Mitt Romney today will step up his criticism of President Obama's foreign policy and his handling of hot spots in the Middle East, as he tries to show a contrast with his rival on Iran, Libya and Syria.

In a speech at the Virginia Military Institute, Romney will seek to cast Obama as weak and responsible for lowering America's standing around the globe. Romney will say that "hope is not a strategy," according to excerpts of his remarks released by his campaign.

"The attacks on America last month should not be seen as random acts," Romney will say, in reference to the deadly violence in Libya that killed U.S. Ambassador Christopher Stevens and three other Americans.

"They are expressions of a larger struggle that is playing out across the broader Middle East," he will say. "These attacks were the deliberate work of terrorists who use violence to impose their dark ideology on others, especially women and girls, who are fighting to control much of the Middle East today and who seek to wage perpetual war on the West."

Romney was criticized by Democrats for his initial harsh reaction to the attack in Benghazi, before it was known that Stevens and the other Americans were killed. He criticized the Obama administration's slowness to call the Libya attack an act of terrorism.

On Iran, Romney will say he won't hesitate to impose new sanctions on that country to thwart its nuclear weapons development and "restore the permanent presence of aircraft carrier task forces" in the eastern Mediterranean and Persian Gulf.

He will also make clear that he would work with U.S. allies to arm rebels seeking to oust Syrian President Bashir Assad -- something that the Obama administration has not done.

"I will work with our partners to identify and organize those members of the opposition who share our values and ensure they obtain the arms they need," Romney will say. "Iran is sending arms to Assad because they know his downfall would be a strategic defeat for them. We should be working no less vigorously ... rather than sitting on the sidelines."

Public opinion polls show Obama has an advantage on foreign affairs, which is not unusual for an incumbent. Obama and Romney will go head-to-head on foreign policy in their last presidential debate on Oct. 22 at Lynn University in Boca Raton, Fla.